HANOVER, N.H. — Farmers from Vermont and New Hampshire told federal officials Tuesday that sweeping food safety rules could sweep them out of business.

About 200 farmers, consumers and others attended a listening session Tuesday hosted by the Food and Drug Administration at Dartmouth College to discuss proposed rules for implementing the 2011 Food Safety Modernization Act.

Among other measures, the rules would require farmers to take new precautions against contamination, including ensuring workers’ hands are washed, irrigation water is clean and animals stay out of fields.

New England farmers have argued that many aspects of the rules were derived from large-scale farming practices that don’t apply to the region’s smaller farms.

“You’re going to have to revamp it, because it sure as hell looks like one size fits all,” said Pooh Sprague, owner of Edgewater Farm in Plainfield, N.H.

Sprague, who grows fruits and vegetables, said he would consider dropping his pick-your-own operation or laying off four to six employees if faced with spending thousands of dollars to comply with water-testing regulations.

“I can’t ramp up and get big,” he said. “We’d have to become leaner and meaner.”

Michael Taylor, a deputy FDA commissioner, told the crowd the goal is to transform the nation’s reactive food safety system into one that prevents illness while also accounting for the wide differences among types of farms.

He outlined various exemptions for smaller farms and said states also can apply for variances if they have alternative safety measures.

“Everybody cares about food safety, for themselves, their families and the businesses you operate,” he said. “We also care about the success of agriculture. ... We’ve got to come to grips with the diversity of agriculture and the diversity of issues that arise in implementing this law.”

He estimated that about 110,000 farms nationwide — or more than half — would be exempt from the rules because their annual sales fall below certain thresholds. But top agriculture officials from both Vermont and New Hampshire said they did not know how many farms in their states would fall under the rules.

Vermont state Sen. David Zuckerman, who runs the Full Moon Farm in Hinesburg, drew laughs when he noted that opposition to the rules has united the “left-wing radicals in Vermont” with the “right-wing libertarians in New Hampshire.”

He also won applause when he argued that the rules were part of a larger effort by corporate farms to drive small farms out of business.

“We wouldn’t eat our own food if we didn’t think it was safe,” he said.

New Hampshire state Rep. Gary Comtois, who owns Sticks and Stones Farm in Barnstead, predicted the rules would wipe out half of New Hampshire’s farms within six years.

“Big farms caused the problem,” he said. “We were like a mosquito, but now with the local movement and people wanting to find out about their food, now we’re a threat.”

The U.S. House voted in June to delay the rules until the FDA conducts a study on their economic impacts. The agency is accepting public comments until Nov. 15.